Image: <bdi><a href="https://www.wikidata.org/wiki/Q56247090" class="extiw" title="d:Q56247090"><span title="mineral collector and dealer">Robert M. Lavinsky</span></a></bdi> (CC BY-SA 3.0)
monoclinicuncommonphosphates
Vivianite
Fe3(PO4)2·8H2O
The image displays a cluster of elongated, prismatic Vivianite crystals, exhibiting a deep blue-green color and a vitreous luster, some appearing almost black due to their depth of color.
Vivianite Physical Properties
Mohs Hardness
1.5Crystal System
monoclinicLuster
vitreousStreak Color
bluish whiteCleavage
perfect on {010}Fracture
fibrousSpecific Gravity
2.65Colors
colorless, blue, blue-green, green, dark blue, blackTransparency
transparentType Locality
Mullica Hill, Gloucester County, New Jersey, USAMineral Group
phosphatesUses
collectorAssociated Minerals
pyrite, siderite, apatite, quartz, clay mineralsRarity
uncommonGeological Context
Vivianite typically forms as a secondary mineral in reducing environments within sedimentary deposits, such as bog iron ores, fossil bones, shells, or wood, where iron and phosphate are present. It can also occur in pegmatites and hydrothermal veins.
